Process for producing syngas using plasma gasifiers

A process for gasification of solid feed material to produce a syngas in a reactor vessel including a bottom section, a top section, and a middle section between the bottom section and the top section, the method comprising:

• providing a plasma heated carbonaceous bed in the bottom section of a reactor vessel;
• feeding feed material into the reactor vessel to form a bed of deposited feed material on top of the carbonaceous bed in the bottom section;
• reacting the feed material with hot gases rising from the bottom section;
• forming, in the middle section of the reactor vessel, a syngas mixture containing a varying quantity of unreacted particles of the feed material, wherein the middle section is configured as a truncated inverse cone that is wider adjacent the top section than adjacent the bottom section and configured to contain the bed of deposited feed material;
• allowing the syngas mixture to rise into the top section of the reactor vessel toward one or more syngas outlets in a roof of the reactor vessel, wherein the top section includes a conical part starting adjacent the middle section that has an overall configuration of a truncated cone that is wider at a higher end of the conical part than adjacent the middle section, the top section including a freeboard region in a lower part of the top section and a quench zone in an upper part of the top section, and wherein the middle section truncated inverse cone has a larger wall angle relative to a center line of the vessel than the wall angle of the conical part of the top section;
• maintaining conditions in the vessel such that unreacted particles from the middle section are subjected to further reactions in the lower part of the top section;
• and
• at least partially quenching, by injecting a quench fluid including water, steam, or a mixture thereof, through a plurality of quench fluid inlets in the roof into a quench zone in the upper part of the top section, at least some of the unreacted particles sufficiently to reduce the number of unreacted particles exiting the reactor vessel that are likely to be deposited on walls of external ductwork.